hadoop-zookeeper-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Ted Dunning <ted.dunn...@gmail.com>
Subject Re: What roles do "even" nodes play in the ensamble
Date Thu, 26 Aug 2010 03:13:11 GMT
Just use 3 nodes.  Life will be better.

You can configure the fourth node in the event of one of the first three
failing and bring it on line.  Then you can re-configure and restart each of
the others one at a time.  This gives you flexibility because you have 4
nodes, but doesn't decrease your reliability the way that using a four node
cluster would.  If you need to do maintenance on one node, just configure
that node out as if it had failed.

On Wed, Aug 25, 2010 at 4:26 PM, Dave Wright <wrightd@gmail.com> wrote:

> You can certainly serve more reads with a 4th node, but I'm not sure
> what you mean by "it won't have a voting role". It still participates
> in voting for leaders as do all non-observers regardless of whether it
> is an even or odd number. With zookeeper there is no voting on each
> transaction, only leader changes.
>
> -Dave Wright
>
> On Wed, Aug 25, 2010 at 6:22 PM, Todd Nine <todd@spidertracks.co.nz>
> wrote:
> > Do I get any read performance increase (similar to an observer) since
> > the node will not have a voting role?
> >
> >
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message